The huge flows of money into the impoverished country had the opposite effect of what was intended, the report said. Instead of bolstering the local government, the gusher of cash flooded the country with money that could not be spent fast enough.

“The large sums of stabilization dollars the United States devoted to Afghanistan in search of quick gains often exacerbated conflicts, enabled corruption, and bolstered support for insurgents,” the document stated.

“By fueling corruption and the population’s disillusionment with its government, the coalition undermined the very government it sought to legitimize and drove support for the insurgency.”

The US and its allies invaded Afghanistan on October 7, 2001 as part of Washington’s so-called war on terror. The offensive removed the Taliban regime from power, but after 17 years insecurity still persists in the country despite the presence of thousands of foreign troops.

After becoming president in 2008, Barack Obama vowed to end the US war in Afghanistan but failed to keep his promise.

President Donald Trump, who had spoken against the Afghanistan war during his election campaign, has also unveiled a strategy which foresees US troops staying in the country for a long haul.